YES Problem: div(X,e()) -> i(X) i(div(X,Y)) -> div(Y,X) div(div(X,Y),Z) -> div(Y,div(i(X),Z)) Proof: DP Processor: DPs: div#(X,e()) -> i#(X) i#(div(X,Y)) -> div#(Y,X) div#(div(X,Y),Z) -> i#(X) div#(div(X,Y),Z) -> div#(i(X),Z) div#(div(X,Y),Z) -> div#(Y,div(i(X),Z)) TRS: div(X,e()) -> i(X) i(div(X,Y)) -> div(Y,X) div(div(X,Y),Z) -> div(Y,div(i(X),Z)) Matrix Interpretation Processor: dim=1 interpretation: [i#](x0) = 4x0, [div#](x0, x1) = 4x0 + x1 + 7, [i](x0) = 3x0 + 1, [div](x0, x1) = 3x0 + x1 + 2, [e] = 2 orientation: div#(X,e()) = 4X + 9 >= 4X = i#(X) i#(div(X,Y)) = 12X + 4Y + 8 >= X + 4Y + 7 = div#(Y,X) div#(div(X,Y),Z) = 12X + 4Y + Z + 15 >= 4X = i#(X) div#(div(X,Y),Z) = 12X + 4Y + Z + 15 >= 12X + Z + 11 = div#(i(X),Z) div#(div(X,Y),Z) = 12X + 4Y + Z + 15 >= 9X + 4Y + Z + 12 = div#(Y,div(i(X),Z)) div(X,e()) = 3X + 4 >= 3X + 1 = i(X) i(div(X,Y)) = 9X + 3Y + 7 >= X + 3Y + 2 = div(Y,X) div(div(X,Y),Z) = 9X + 3Y + Z + 8 >= 9X + 3Y + Z + 7 = div(Y,div(i(X),Z)) problem: DPs: TRS: div(X,e()) -> i(X) i(div(X,Y)) -> div(Y,X) div(div(X,Y),Z) -> div(Y,div(i(X),Z)) Qed